You will get a lot of traction here from Slices - the ability to specify a subset of an array. The actual structure is a little obtuse to me, but you''l probably want something like:

##################################
# Add on File B's data
for my  $i ( 0 ..  $#H_USES ) {
$HoA{$H_USES[$i][5]} = [@{$H_USES[$i]}[0, 1, 3 .. $#{$H_USES[$i]}]];
} # end looping over rows
##################################
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You'd have something cleaner if you don't mind being destructive, because you can use splice:

##################################
# Add on File B's data
for my  $i ( 0 ..  $#H_USES ) {
splice(@{$H_USES[$i]},2,1); # Eliminate 1 field at location 2
$HoA{$H_USES[$i][5]} = $H_USES[$i];
} # end looping over rows
##################################
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